This invention relates to apparatus for processing photosensitive materials, such as sheets of x-ray film.
The processing apparatus disclosed in the before-mentioned copending U.S. patent application includes an upper tank and a lower tank for holding a processing fluid. The tanks are located on opposite sides of a processing device, and fluid can flow from the tanks into a narrow processing chamber through which a sheet of photosensitive material is advanced for processing of latent images on the material. The processing fluid is delivered by a pump to fluid distributors in the upper tank. Fluid can flow from the upper tank to the lower tank.
It is known that aeration and air entrapment can cause degradation of the chemistry of a processing solution. Thus, it is desirable to reduce or eliminate the aeration or entrapment of air in such solutions. Air entrapment occurs any time the processing solution experiences a free-fall condition. In the apparatus disclosed in the before-mentioned application, aeration and air entrapment can occur because processing solution is delivered from the pump into the upper tank and it free-falls into the lower tank. Also, aeration of a processing solution is a function of the amount of fluid surface area exposed to air. Accordingly, if the surface area exposed to air can be reduced, the resulting aeration also is reduced.
Another concern is the cost of manufacture of a processing apparatus. Accordingly, it is desirable to eliminate portions of a processing apparatus whenever such can be accomplished without loss of reliability, quality or important features.